nuovo sito fatto con pelican
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# -*- coding: utf-8 -*-
"""
events plugin for Pelican
=========================
This plugin looks for and parses an "events" directory and generates
blog posts with a user-defined event date. (typically in the future)
It also generates an ICalendar v2.0 calendar file.
https://en.wikipedia.org/wiki/ICalendar
Author: Federico Ceratto <federico.ceratto@gmail.com>
Released under AGPLv3+ license, see LICENSE
"""
from datetime import datetime, timedelta
from pelican import signals, utils
from collections import namedtuple, defaultdict
import icalendar
import logging
import os.path
import pytz
log = logging.getLogger(__name__)
TIME_MULTIPLIERS = {
'w': 'weeks',
'd': 'days',
'h': 'hours',
'm': 'minutes',
's': 'seconds'
}
events = []
localized_events = defaultdict(list)
Event = namedtuple("Event", "dtstart dtend metadata rrule")
def parse_tstamp(ev, field_name):
"""Parse a timestamp string in format "YYYY-MM-DD HH:MM"
:returns: datetime
"""
try:
return datetime.strptime(ev[field_name], '%Y-%m-%d %H:%M')
except Exception as e:
log.error("Unable to parse the '%s' field in the event named '%s': %s" \
% (field_name, ev['title'], e))
raise
def parse_timedelta(ev):
"""Parse a timedelta string in format [<num><multiplier> ]*
e.g. 2h 30m
:returns: timedelta
"""
chunks = ev['event-duration'].split()
tdargs = {}
for c in chunks:
try:
m = TIME_MULTIPLIERS[c[-1]]
val = int(c[:-1])
tdargs[m] = val
except KeyError:
log.error("""Unknown time multiplier '%s' value in the \
'event-duration' field in the '%s' event. Supported multipliers \
are: '%s'.""" % (c, ev['title'], ' '.join(TIME_MULTIPLIERS)))
raise RuntimeError("Unknown time multiplier '%s'" % c)
except ValueError:
log.error("""Unable to parse '%s' value in the 'event-duration' \
field in the '%s' event.""" % (c, ev['title']))
raise ValueError("Unable to parse '%s'" % c)
return timedelta(**tdargs)
def parse_recursion(ev, field_name):
"""
Parse information about recurring events and return frequency of event and untill time.
"""
chunks = ev[field_name].split()
freq = chunks[0].upper()
if 'until' in chunks:
until = datetime.strptime(chunks[-1], '%Y-%m-%d')
rrule = [freq, until]
else:
rrule = [freq]
return rrule
def parse_article(generator, metadata):
"""Collect articles metadata to be used for building the event calendar
:returns: None
"""
if 'event-start' not in metadata:
return
dtstart = parse_tstamp(metadata, 'event-start')
rrule=[]
if 'event-end' in metadata:
dtend = parse_tstamp(metadata, 'event-end')
elif 'event-duration' in metadata:
dtdelta = parse_timedelta(metadata)
dtend = dtstart + dtdelta
if 'event-recurring' in metadata:
rrule = parse_recursion(metadata, 'event-recurring')
else:
msg = "Either 'event-end' or 'event-duration' must be" + \
" speciefied in the event named '%s'" % metadata['title']
log.error(msg)
raise ValueError(msg)
events.append(Event(dtstart, dtend, metadata, rrule))
def generate_ical_file(generator):
"""Generate an iCalendar file
"""
global events
ics_fname = generator.settings['PLUGIN_EVENTS']['ics_fname']
if not ics_fname:
return
if not os.path.exists(generator.settings['OUTPUT_PATH']):
os.makedirs(generator.settings['OUTPUT_PATH'])
ics_fname = os.path.join(generator.settings['OUTPUT_PATH'], ics_fname)
log.debug("Generating calendar at %s with %d events" % (ics_fname, len(events)))
tz = generator.settings.get('TIMEZONE', 'UTC')
tz = pytz.timezone(tz)
ical = icalendar.Calendar()
ical.add('prodid', '-//My calendar product//mxm.dk//')
ical.add('version', '2.0')
DEFAULT_LANG = generator.settings['DEFAULT_LANG']
curr_events = events if not localized_events else localized_events[DEFAULT_LANG]
for e in curr_events:
#force convert to ical format here, because otherwise it doesn't happen?
from icalendar import vDatetime as vd
dtend = vd(e.dtend).to_ical()
dtstart = vd(e.dtstart).to_ical()
dtstamp = vd (e.metadata['date']).to_ical()
ie = icalendar.Event(
summary=e.metadata['title'],
dtstart=dtstart,
dtend=dtend,
dtstamp= dtstamp,
priority=5,
uid=e.metadata['title'],
)
if 'event-location' in e.metadata:
ie.add('location', e.metadata['event-location'])
if 'event-recurring' in e.metadata:
if len(e.rrule)>=2:
ie.add('rrule', {'freq':e.rrule[0],'until':e.rrule[1]})
else:
ie.add('rrule', {'freq':e.rrule[0]})
ical.add_component(ie)
with open(ics_fname, 'wb') as f:
f.write(ical.to_ical())
def generate_localized_events(generator):
""" Generates localized events dict if i18n_subsites plugin is active """
if "i18n_subsites" in generator.settings["PLUGINS"]:
if not os.path.exists(generator.settings['OUTPUT_PATH']):
os.makedirs(generator.settings['OUTPUT_PATH'])
for e in events:
if "lang" in e.metadata:
localized_events[e.metadata["lang"]].append(e)
else:
log.debug("event %s contains no lang attribute" % (e.metadata["title"],))
def generate_events_list(generator):
"""Populate the event_list variable to be used in jinja templates"""
if not localized_events:
generator.context['events_list'] = sorted(events, reverse = True,
key=lambda ev: (ev.dtstart, ev.dtend))
else:
generator.context['events_list'] = {k: sorted(v, reverse = True,
key=lambda ev: (ev.dtstart, ev.dtend))
for k, v in localized_events.items()}
def initialize_events(article_generator):
"""
Clears the events list before generating articles to properly support plugins with
multiple generation passes like i18n_subsites
"""
del events[:]
localized_events.clear()
def register():
signals.article_generator_init.connect(initialize_events)
signals.article_generator_context.connect(parse_article)
signals.article_generator_finalized.connect(generate_localized_events)
signals.article_generator_finalized.connect(generate_ical_file)
signals.article_generator_finalized.connect(generate_events_list)